Microstructure and thermodynamics of inhomogeneous polymer blends and solutions.

A free energy density functional theory (DFT) for nonuniform polymeric mixtures is proposed based on first order thermodynamic perturbation theory. The segment-density based free energy functional provides an accuracy comparable to the numerically intensive polymeric DFTs while preserving the computational simplicity of an atomic DFT. The presented applications for solutions and blends of branched and linear polymers demonstrate the capability of the theory to capture the entropic and enthalpic effects governing the microstructure.